Use strong over b for improved a11y semantics

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

src/components/views/dialogs/devtools/SettingExplorer.tsx

@@ -128,7 +128,7 @@ const EditSetting: React.FC<IEditSettingProps> = ({ setting, onBack }) => {
             </h3>
 
             <div className="mx_DevTools_SettingsExplorer_warning">
-                <b>{_t("devtools|caution_colon")}</b> {_t("devtools|use_at_own_risk")}
+                <strong>{_t("devtools|caution_colon")}</strong> {_t("devtools|use_at_own_risk")}
             </div>
 
             <div>